Hearing loss varies widely from patient to patient in type and severity. As a result, the acoustical characteristics of a hearing aid must be selected to provide the best possible result for each hearing impaired person. Typically, these acoustical characteristics of a hearing aid are “fit” to a patient through a prescription procedure. Generally, this has involved measuring hearing characteristics of the patient and calculating the required amplification characteristics based on the measured hearing characteristics. The desired amplification characteristics are then programmed into a digital signal processor in the hearing aid, the hearing aid is worn by the patient, and the patient's hearing is again evaluated while the hearing aid is in use. Based on the results of the audiometric evaluation and/or the patient's comments regarding the improvement in hearing, or lack thereof, an audiologist or dispenser adjusts the programming of the hearing aid to improve the result for the patient.
As one would expect, the fitting procedure for a hearing aid is generally an interactive and iterative process, wherein an audiologist or dispenser adjusts the programming of the hearing aid, receives feedback from the patient, adjusts the programming again, and so forth, until the patient is satisfied with the result. In many cases, the patient must evaluate the hearing aid in various real world situations outside the audiologist's or dispenser's office, note its performance in those situations and then return to the audiologist or dispenser to adjust the hearing aid programming based on the audiologist's or dispenser's understanding of the patient's comments regarding the patient's experience with the hearing aid.
One of the significant factors in the price of a hearing aid is the cost of the audiologist's or dispenser's services in performing audiometric testing of the patient, and fitting and programming the device, along with the necessary equipment, such as software, computers, cables, interface boxes, etc. If the required participation of the audiologist and/or dispenser and the fitting equipment can be eliminated or at least significantly reduced, the cost of a hearing aid can be significantly reduced. Also, if the amount and complexity of equipment needed to perform testing and fitting can be reduced, the cost passed along to the patient is reduced.
What is needed, therefore, is a programmable hearing assistance device that includes a built-in audiometric testing mode for performing an audiometric testing procedure and for automatically programming the amplification frequency response of the device based on the results of the testing procedure.